Digital Edition

Scientists raise fiber-optic limits

Scientists from Lucent Technologies' Bell Labs in Murray Hill, NJ, have recently determined that the theoretical capacity of optical fiber is 10 times greater than what had previously been thought.The...

Scientists from Lucent Technologies’ Bell Labs in Murray Hill, NJ, have recently determined that the theoretical capacity of optical fiber is 10 times greater than what had previously been thought.

The researchers, who published their findings in the British journal Nature, say the maximum amount of information that can theoretically be sent over optical fiber is about 100 terabits of data per second over a single strand of fiber — the equivalent of roughly 20 billion one-page e-mails.

Lucent executives said the finding indicates that fiber optics will be capable of meeting the future demand for services such as high-speed Internet access and “bandwidth-hungry” applications like video-on-demand.

“This paper highlights the fundamental understanding of the ultimate capacity of fiber,” said Alastair Glass, CTO of Lucent’s Optical Networking Group. “It says that we are still a long way from the fundamental limits in current commercial systems, and it’s still uncertain when optical systems will be able to approach the theoretical limits.”

Current commercial optical systems can send information at a rate of just under two terabits of information per second, and rates of 10 terabits per second (Tb/s) have been demonstrated in laboratory experiments. Scientists have found it difficult to theoretically calculate how much information can be transmitted over a glass fiber because the physical properties of glass make light transmitted over fiber susceptible to “scrambling” in a very complicated fashion.